What do the following two equations represent? $-x-2y = 2$ $2x-y = 4$
Answer: Putting the first equation in $y = mx + b$ form gives: $-x-2y = 2$ $-2y = x+2$ $y = -\dfrac{1}{2}x - 1$ Putting the second equation in $y = mx + b$ form gives: $2x-y = 4$ $-y = -2x+4$ $y = 2x - 4$ The slopes are negative inverses of each other, so the lines are perpendicular.